OBJECT OF THE HISTORY OF EVOLUTION. 5 



to present this branch of the science in as popular a form as 

 possible. A satisfactory general idea of the course of the 

 evolution of the human embryo can, indeed, be given without 

 going very deeply into anatomical details. As numerous 

 successful attempts have recently been made to awaken 

 the interest of larger classes of educated persons in other 

 branches of Science, I also may hope to succeed in this 

 department, though it is in many respects especially beset 

 with difficulties. 



The History of the Evolution of Man, as it has been 

 usually treated in lectures for medical students at the 

 universities, has only concerned itself with Embryology,' 

 so-called, or more correctly with Ontogeny,* in other words, 

 with the history of the evolution of individual human 

 organisms. This, however, is only the first part of the task 

 before us, only the first half of the History of the Evolution 

 of Man in the wider sense which will here be attributed 

 to the term. The second part, equal in importance and 

 interest, is Phylogeny,^ which is the history of the evolution 

 of the descent of man, that is, of the evolution of the 

 various animal forms through which, in the course of count- 

 less ages, mankind has gradually passed into its present 

 form. All my readers know of the very important scientific 

 movement which Charles Darwin caused fifteen years ago, 

 by his book on jthe Origin of Species. The most important 

 direct consequence of this work, which marks a fresh epoch, 

 has been to cause new inquiries to be made into the 

 origin of the human race, which have proved the natural 

 evolution of man through lower animal forms. The Science 

 ' which treats of the development of the human race from 

 the animal kingdom is called Phylogeny, or the tribal 



